“The Cocktail Effect” is the title of a study just published by PAN[1], the Pesticide Action Network and the Soil Association. And you guessed right, this is not about what too many Bloody Marys will do to your head in the morning and your liver in the long term, but about the ‘cocktail of pesticides’ we are exposed to every day. The UK government routinely tests for pesticide residue in food and the results make very uncomfortable reading: “Of the 3,357 total number of samples tested by the government in 2017, more than a quarter (26%) contained residues of multiple pesticides. Of the 1,883 samples of fruit and vegetables tested, 40% contained residues of multiple pesticides.” Over all 110 different ‘active ingredients’ were found, including “… 39 ‘known’, ‘probable’ or ‘possible’ human carcinogens. 24 suspected Endocrine Disrupting Chemicals (EDCs) which interfere with hormone systems and can cause cancerous tumours, birth defects, and other developmental disorders. 16 developmental, reproductive or neurotoxins. Developmental and reproductive toxins have adverse effects on sexual function and fertility in children and adults while neurotoxins have negative impacts on brain development, the nervous system and nerve tissue. 11 cholinesterase inhibitors which affect the nervous system”.

And now for the bad news: When different chemicals are combined they can become more toxic than each active ingredient on its own. The PAN/Soil Association report has looked at the available studies on human cells and tissues and concludes “that combined actions of pesticide mixtures can lead to the creation of cancer cells and disruption of the endocrine system, which produces hormones that regulate metabolism, growth and development, tissue function, sexual function, and reproduction, among other things. Studies conducted on mice and rats have revealed similar results. Pesticide mixtures have been associated with obesity and impaired liver function, even when the doses of individual chemicals are below the safety levels set by regulators”.

And here is why the combination of several chemicals can be more toxic than each component on its own: Take for example glyphosate: scientists who did experiments with mice using ‘only’ glyphosate, the active ingredient in the Roundup herbicide, found that it had little or no impact. But if the mice were given Roundup, the combination of glyphosate and additives called ‘adjuvants’, the same dose became toxic and in the long run was likely to cause cancer. Roundup is a herbicide, it’s designed to kill plants and the additives make the active ingredient – glyphosate – work better: they make it water soluble (so that it is easy to spray), and fat soluble – otherwise glyphosate could not penetrate the protective wax coating on the leaves and kill the plants. Qualities like these turn ‘adjuvants’ into ‘the master key’ that allows glyphosate to enter cells, damage the DNA and alter genes.

Roundup is just one herbicide farmers (and some gardeners still) use, other agrochemicals are needed to kill pests like mites or aphids or deal with fungal infections. According to the PAN/Soil Association report, 400 different pesticides are licensed for use in the UK. The industry claims that pesticide use has gone down over the years – which is correct if you measure chemicals by weight. What the companies don’t tell you is that the toxicity of their products has increased. That’s why farmers use less per application. In the PAN/Soil Association report a case study from a UK farmer illustrates what this looks like in practice. On the 530 hectares farm growing wheat, barley, oil seed rape and peas 32 to 40 different pesticides were used, a single crop, like wheat, would be sprayed with a dozen different active ingredients.

It is not surprising that pesticide residue can be found in our water, in the soil, in wild animals, in insects and of course in our bodies, too. And keep in mind: we are not just exposed to agrochemicals, there are household chemicals, paints, microplastics …. the list is long, the possible combination of substances is infinite and while our liver and kidneys may get rid of some of them, others are stored in our fat tissue.

Not least because of the cocktail effect there is no threshold, no amount of any chemical in our food that can be deemed ‘safe’ to consume. All we can do is reduce our exposure. In that regard Halloween 2019 is a very good day: Britain has not left the EU and therefore EU regulatory standards still apply. The European Court of Justice has just ruled that pesticide formulas (and not just the active ingredients) have to be tested before a licence can be given. The ‘precautionary principle’ applies and existing licenses could be withdrawn.

The PAN/Soil Association report mentions the immense pressure to loosen regulations Britain is likely to face in future trade talks with the US. And the organizations add a wish list of measures the UK could take to protect our health and the environment better than EU rules do at present. Personally, I’d expect the likelihood of the latter happening to be about as high as sitting next to a unicorn on a bus.

If that all sounds rather bleak – there is one thing we all can do: eat organic wherever and whenever we can, and not just fruit and vegetables, but bread, pasta, dairy products and meat too. There is no guarantee that these products will be pesticide free. Certified organic farms are not allowed to use chemical pesticides but our environment is so polluted that cross-contamination is always a possibility. But eating organic food is our one and only chance to limit our pesticide exposure.

I’ll drink an (organic) Bloody Mary to that.

[1] The full report is available at: https://tinyurl.com/y6zy5k3x

Marianne Landzettel is a journalist writing and blogging about food, farming and agricultural policies in the UK, the US, continental Europe and South Asia. She worked for the BBC World Service and German Public Radio for close to 30 years.

Follow her on twitter at @M_Landzettel

Images (c) and used with kind consent @M.Kunz

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